Abstract: A miniature circulator which is microwave integrated circuit compatible and based on microstrip transmission techniques is described. The circulator includes a dielectric or semiconductor substrate having microstrip transmission lines formed thereon and a patterned metalization formed as the node metalization for the circulator. The substrate may carry other circuits such as power combiners, amplifiers, and switches. The substrate further includes monolithic capacitors over the substrate at the center of the circulator in a first embodiment or disposed along the periphery of the patterned metalization in the second embodiment. The capacitors are used to capacitively couple the patterned metalization or node metalization to the ground plane conductor. The value of capacitance is selected to provide value broadband performance.